1. Field of the Invention
This invention relates to a novel tubular display package of the type comprising an elongated substantially solid light transmissive plastic tube having a plurality of closed ended channels formed longitudinally within the tube with a light affecting material contained within more than one of the channels. More particularly, the present invention relates to a multiplicity of intertwined helical channels for containing a luminescent product.
2. Description of Related Art
Various types of packages have been proposed for containing light-producing or light effecting materials. Generally, such packages comprise an elongated tube or tube-like container formed of plastic or other material which is sealed at both ends to create an interior volume for holding a quantity of the light affecting material. Such packages are often fabricated from extruded plastic. Among the wide variety of liquid products that may be contained in such tubular packaging is a range of luminescent, bioluminescent or chemiluminescent compositions.
One such form of tubular packaging has found application in chemical lightsticks of the type described in U.S. Pat. No. 3,576,987. In this type of arrangement, an outer flexible sealed tube contains components of a chemiluminescent mixture separated by a frangible glass vial inside the tube. By bending the tube, the frangible vial is broken, causing the components to mix and form a chemiluminescent mixture which emits light. The reaction transfers chemical energy to a fluorescer which will emit a characteristic wavelength of light in the range of 350-1000 nanometers. The art of generating colored light via chemical energy, by the reaction of an oxalic acid ester with hydrogen peroxide in the presence of a fluorescer compound in organic solvents has been disclosed in U.S. Pat. Nos. 3,816,326; 3,781,329; and 3,704,309. These types of chemical lightsticks find particular application as safety devices for use by persons under low-light conditions. Heretofore, however, all such lightstick applications have been limited to a single volume or channel within the chemical lightstick which produces but a single color.
Another typical, but by no means exclusive, application of luminescent tubular displays and their associated packaging is in connection with chemiluminescent jewelry. In these applications, chemical formulations of the type noted above are packaged as jewelry, e.g., necklaces, bracelets and earrings, to provide not only an attractive display, but also a wearable safety device for use by persons under low-light conditions. These types of wearable packages produce light with no external power source, emit no heat, and operate under all conditions, including in inclement weather and under water.
Generally, these products are fabricated from elongated flexible plastic tubing having an axially extending interior bore or channel. Numerous transparent dyes may also be embedded in the polymer matrix of the package shift the wavelength of the light, emitted or reflected light. Typical colorants which may be used in the present invention have a spectural emission falling between 330-1000 nanometers. Many fluorescent compounds having these properties are fully described in Fluorescence and Phosphorescence by Peter Pringsheim, Interscience Publishers, Inc., New York, New York, 1949. One commercial embodiment of such a product has been marketed under the name NECKLITES by World Plastic Corp., Cincinnati, Ohio.
Generally, light activation in the above-noted types of devices is of two basic types. In one type, a frangible glass ampule contains one component of the chemiluminescent system, with the remaining component of the chemiluminescent system being contained within the single channel inside the tube. When the ampule is broken, as by bending the tube, the chemiluminescent materials mix together producing visible light as described above. A second approach premixes the chemiluminescent materials, but maintains the tubular packaging at a very low temperature by means of dry ice or the like to inhibit the chemical reaction until the display is used. Typical examples of these types of containers are described in U.S. Pat. Nos. 4,508,642 and 4,061,910. Heretofore, the present art of packaging such chemiluminescent formulations has been confined to displaying only one visible color per container. In order to produce multiple color effects, it has been necessary for the user to purchase multiple tubes of different colors and link them together, for example in a "daisy chain" using red, white and blue for Fourth of July events. Consequently, a need has existed for a self-contained tubular display package which is capable of producing multiple optical effects, such as different colors.
Another problem encountered in some prior art light emitting tubular packages is caused by the fairly thin 1.59 mm. (1/16 inch) interior diameter of the tubular packaging. Because of the relatively small interior diameter, the amount of luminescent liquid contained within the package is limited, thereby achieving a relatively low light level. The limited light output of this type of packaging has created a strong demand for larger diameter tubing in order to achieve higher light output, but the costs of doubling the inside diameter of the tubing, for example, results in an exponential increase in the quantity and thus the resulting cost of the luminescent liquid needed to fill the package. The disposable nature of this type of luminescent system, however, does not provide sufficient support in the marketplace for such exponential increases in the cost of the materials associated with this type of product. Although a type of display package called a "Jumbo" necklace has shown the demand for larger diameter products, the market has been limited by the cost of the luminescent liquid necessary to fill this size package.
Consequently, a need exists for a tubular display package capable of producing multiple optical effects, and in particular a display which can produce two or more visually discernable colors from the same package. Further, a need exists for a tubular display package which can produce a greater light output, particularly for use under low light conditions, without a disproportionately large increase in the amount of luminescent liquid required. From the detailed description which follows, it will become clear that to advance the state-of-the-art, it is necessary that the types of extruded tubular packages described herein have multiple internal channels. It will further become apparent that the position, volume and number of these channels have the capability of varying independently within the package.
Finally, while the state-of-the-art, as well as exemplary applications of the present invention, are described herein in connection with lightsticks and jewelry, it will be understood that the improvements contemplated by the present invention may be incorporated in any light transmissive tubular package to exhibit the light affecting materials within multiple channels incorporated in the package.